Add to ORKGHabermas and Apel share with the wittgensteinian linguistic turn the main issue which is at stake in the latter. That is: they rely on the linguisticalpragmatic substitution of the traditional Cartesian (and Kantian) subject of representation, thought as the nonempirical and non-objective pre-condition of the possibility of the objective world, with the function of linguistic and communicative interaction as a means of subjective and intersubjective world-disclosure (H. Sluga 1996; Wittgenstein, Tlp, § 5.54- 5.55). The issue basically concerns the way we think about language as a system and a means of representation. What is here at stake is actually the source of its normativity, and the way in which this normativity can be rationally fou...